Have a look at the FLENS site:

    http://flens.sourceforge.net

You can find there

 - Notes about how to configure and install FLENS
 - Tutorial slides showing:
     + how to use FLENS
     + how FLENS works
     + how easy it is to extend FLENS
 - Join the FLENS mailing list at

      https://imap.uni-ulm.de/lists/info/flens

   if ...
     + ... you want to be informed about new releases
     + ... you have problems with FLENS
     + ... you have any feature requests

